fix(worker): normalize model alias before preset lookup, wire DefaultMaxTurns as fallback

A full model id like claude-sonnet-4-6 in list_config.model never matched any
ModelPresets row (only bare aliases did), so every run under it landed on the
hardcoded 30-turn/DefaultLevel fallback instead of the sonnet preset row -
this is what killed two autonomous tasks at the 30-turn limit.

ModelRegistry.TryNormalizeAlias (non-throwing: exact match, then substring
match against a full model id) lets ModelPresets.For resolve a full model id
to its alias's preset row. For a model that still doesn't resolve, the
hardcoded 30 is replaced by a caller-supplied fallbackMaxTurns, and TaskRunner
now passes AppSettings.DefaultMaxTurns there - so that setting has a real
effect instead of being dead, matching the direction already noted in
docs/open.md.

src/ClaudeDo.Worker/CLAUDE.md

@@ -122,7 +122,7 @@ A child that hits a roadblock (fails, or reports `CLAUDEDO_BLOCKED` roadblocks)
 1. Load task + list metadata from DB; resolve config from `list_config` + task-level overrides (model, system_prompt, agent_path)
 2. Create worktree (if `WorkingDir` set) or sandbox directory
 3. Mark task "running", broadcast `TaskStarted`
-4. Resolve the effective model (task → list → `AppSettings.DefaultModel`), then take its `ModelPresets` row: the preset supplies `--effort` and the **global** max-turns default (task/list `MaxTurns` overrides still win). Build CLI args via `ClaudeArgsBuilder`; inject attachment absolute paths via `TaskPromptComposer.Compose` (appends a read-only "## Reference files" section); invoke `ClaudeProcess` with task prompt
+4. Resolve the effective model (task → list → `AppSettings.DefaultModel`), then take its `ModelPresets` row via `ModelPresets.For(global.ModelPresets, model, global.DefaultMaxTurns)`: the model string is resolved through `ModelRegistry.TryNormalizeAlias` first, so a full CLI model id (e.g. `claude-sonnet-4-6`, not just the bare `sonnet`/`opus`/`haiku`/`fable` aliases) still hits its alias's preset row; only a truly unrecognized model falls back to a synthesized row using `AppSettings.DefaultMaxTurns` (never a hardcoded number, and never throws — an unknown model must not block a run). The preset supplies `--effort` and the **global** max-turns default (task/list `MaxTurns` overrides still win). Build CLI args via `ClaudeArgsBuilder`; inject attachment absolute paths via `TaskPromptComposer.Compose` (appends a read-only "## Reference files" section); invoke `ClaudeProcess` with task prompt
 5. Stream NDJSON output through `StreamAnalyzer`; lines forwarded to log file and SignalR (`TaskMessage`)
 6. On success: auto-commit changes (worktree only), store run record, mark "done"
 7. On failure: retry once if session ID available (`--resume`), then mark "failed"

src/ClaudeDo.Worker/Runner/TaskRunner.cs

@@ -519,7 +519,7 @@ public sealed class TaskRunner
         // The model decides the global effort/turn defaults: one preset row per model alias
         // (Settings → General). List- and task-level max-turns overrides still win.
         var model = task.Model ?? listConfig?.Model ?? global.DefaultModel;
-        var preset = Data.Models.ModelPresets.For(global.ModelPresets, model);
+        var preset = Data.Models.ModelPresets.For(global.ModelPresets, model, global.DefaultMaxTurns);
 
         return new ClaudeRunConfig(
             Model: model,